Commercial vehicles have suspension systems which differ from passenger vehicles in their construction and response to vibration. Oftentimes, suspension systems in commercial vehicles are specially designed for the intended use of the commercial vehicle. Large trucks, for example, handle heavy loads and when trade offs arise between work capability of a commercial vehicle and an occupant's comfort, the decision is usually made to favor the performance capability of the commercial vehicle. As a result, occupants of commercial vehicles, which include drivers, suffer from aggravated discomfort and fatigue arising from exposure to vehicle vibrations. It is well known to provide some sort of amelioration of vibration-induced problems, usually associated with the seating for the driver, and less often for the other vehicle occupants. Frequently, commercial vehicles are operated with only a single occupant, the driver, and improvements in seating have focused to a large extent on driver's seats. The goal of ameliorating systems is to selectively absorb vibrational energy and to channel or dissipate the unwanted energy away from the driver's anatomy. Usually, vibrations arriving at a driver's seat bear directional characteristics, and improvements to seating designs take advantage of this fact by restricting seating improvements to a particular type of vibration problem. For example, seating improvements have been directed to improvements in providing fore and aft isolation and vertical isolation. By focusing isolation systems in this manner, it is hoped that the size of the isolation systems will not be so large as to require modification of the vehicle, due to increased height under a passenger's seat, for example.
It is an object of the present invention to provide fore and aft isolation and vertical isolation for new and existing seating arrangements.
Another object of the present invention is to provide improvements in the amount of isolation, using inexpensive components and cost-effective fabrication techniques.
A further object of the present invention is to provide a user-selectable control over the fore and aft motion of the seating system.
Yet another object of the present invention is to provide automatic adjustment of fore and aft motion control and vertical motion control proportional to the weight of the driver.